IMMUNOLOGICAL MEDICINETaylor Francishttps/.doi.org/.10.1080/25785826.2023.2210366Taylor Francis GroupREVIEW ARTICLEOPEN ACCESSCheck for updatesClinical practice guideline for activated phosphatidyl inositol 3-kinase-delta syndrome in JapanKunihiko MoriyaD,Kanako Mitsui-Sekinaka,Yujin SekinakaD,Akifumi Endo,HirokazuKaneganeD,Tomohiro MorioD,Kohsuke Imai and Shigeaki NonoyamaDepartment of Pediatrics,National Defense Medical College,Saitama,Japan;Clinical Research Center,Tokyo Medical andDental University Hospital,Tokyo,Japan;Department of Child Health and Development,Graduate School of Medicine,TokyoMedical and Dental University (TMDU),Tokyo,Japan;Department of Pediatrics and Developmental Biology,Graduate School ofMedicine,Tokyo Medical and Dental University (TMDU),Tokyo,JapanABSTRACTARTICLE HISTORYActivated phosphatidyl inositol 3-kinase-delta syndrome (APDS)due to gain-of-function variReceived 25 January 2023ant in the class IA PI3K catalytic subunit p1108 (responsible gene:PlK3CD)was described inAccepted 24 April 20232013.The disease is characterized by recurrent airway infections and bronchiectasis.It isassociated with hyper-lgM syndrome due to the defect of immunoglobulin class switchKEYWORDSrecombination and decreased CD27-positive memory B cells.Patients also suffered fromAPDS:hyper-lgM syndrome;immune dysregulations,such as lymphadenopathy,autoimmune cytopenia or enteropathy.immune dysregulations;diagnostic flow chartT-cell dysfunction due to increased senescence is associated with a decrease in CD4-positiveT lymphocytes and CD45RA-positive naive T lymphocytes,along with increased susceptibilityto Epstein-Barr virus/cytomegalovirus infections.In 2014,loss-of-function (LOF)mutation ofp85(responsible gene:PlK3R1),a regulatory subunit of p1108,was identified as a causativegene,followed in 2016 by the identification of the LOF mutation of PTEN,which dephos-phorylates PIP3,leading to the differentiation of APDS1(PIK3CD-GOF),APDS2(PIK3R1'-LOF)and APDS-L (PTEN-LOF).Since the pathophysiology of patients with APDS varies with a widerange of severity,it is crucial that patients receive appropriate treatment and managementOur research group created a disease outline and a diagnostic flow chart and summarizedclinical information such as the severity classification of APDS and treatment options.1.Introductioncytomegalovirus (CMV)infections.Flow cytometryInborn errors of immunity (IEI)are a group of dis-analysis of peripheral blood lymphocytes shows T.orders that cause increased susceptibility to infec-cell dysfunction decrease in CD4-positive T lympho-tions and immune dysregulation.To date,variantscytes and CD45RA-positive naive T lymphocytes,decrease in CD27-positive memory B cells andof almost 500 responsible genes have been shown tocause various IEI [1].Activated phosphatidyl inosi-increase in CD24-high CD38-high CD10-positivetransitional B cells [2,3].tol 3-kinase (PI3K)-delta syndrome (APDS)is anFurthermore,in 2014,a loss-of-function variantIEI fo
